Control system.



K. A. SIMMON & A. J. HALL CONTROL SYSTEM.

APPHCATION man JUNE 9, 1914.

1,232,863. Patented July 10, 1917.

3 SHEETS-SHEET 1.

OIOIOOGOUIO'IIOOll I Fa n 0 \ZZIETNESSES' I N d] C, lwvE as' 5 2 E W M Ir I ATTORNEY K. A. SIMMON & A. J. HALL.

CONTROL SYSTEM.

APPLICATION FILED JUNE 9, 3914.

1,232,863. Patented July 10, 1917.

3 SHEETS-SHEET 2.

WITNESSES: INVENTORS w M Q V I: I M MAW K. A. 'SIMMON & A. I. HALL.

CONTROL SYSTEM.

APPLICATION FILED JUNE 9, 1914.

1,232,863. Patented. July 10, 1917.

3 SHEET$SHEET 3- WITNESSES:

INVENTOR ff J? 15. Z; 9 5 9: M gy) J. on

' I ATTORNEY ,U ITED STATES PATE T OFFICE.

KARL A. SIMMON AND ARTHUR J. HALL,'OF WILKINSBURG, PENNSYLVANIA, AssIGN-OBS TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORA- TIONOF PENNSYLVANIA.

CONTROL SYSTEM.

Patented July 10, 1917.

Application filed June 9, 1914. SerialNo. 843,929.

- To all whom it mag concern:

Be it known that we, KARL A. SIMMON, a citizen ofthe' United States, anda resident of Wilkinsburg, in the county of Allesources of energythrough the agency of so called phase-converters which serve to convertsingle-phase energy into polyphase energy during motor operation andpolyphase energy into singlephase energy dur-. ing regenerative periods;

One of the objects of our invention is to provide a system of theabove-indicated class which shall be simple in arrangement and reliableand effective in operation and which shall be adapted to automaticallycompensate for the inherent phase distortion and reduction of voltage ofthe phase converter under conditions of load, irrespective of whether itbe a motor load or a generator loadf Another object of our invention isto provide a control system for a dynamo-electric machine which isconnected to a single-phase source of energy through'the medium of aphase converter, the excitation and phase distortion of. which may beregulated by shifting the connections of the converter with respect tothe source of-energy and, moreover, to provide an auxiliary means forautomatically and concurrently varying the excitation and the phaseposition of the converter by effecting adjustments of the converterconnections to the source of energy.

In a copending application, Serial No. 808,714, filed December 26,1913,by Ben amin G. Lamme and assigned to the Westinghouse Electric &Mfg. Company, a system of the general type referred to is disclosed, andmanually operated switches are provided for adjusting the phaseconverter connections to the source of energy for the purpose of makingcorrections for the reduction in excitation and the displacement inphase position of the converter, under load condit ons. In this system,balanced load conditlons could only be maintained through themanlpulation of the switching device by an operator, who mustnecessarily give his attention to some indicating means in' order tomake the proper adjustments for securing the desired end. i

It is the purpose of our present invention to relieve the operator ofthis duty, and to provide means vfor accomplishing it automatically insuch manner that the desired conditions shall be maintained at alltimes, lrrespective of the nature of the load.

Our invention may best be understood by reference to the accompanyingdrawings, in which Figure 1 is a diagrammatic view of the maincircuitsof a system of control embodying our invention; Fig. 2 is adiagrammatic View of the auxiliary control circuits of our system, thecontrol circuits being segregated from the main circuits for the sake ofsimplicity in the diagrams and clearness in understanding the system andits operation; Fig. 3 is a chart showing the sequence of switches in thevarious positions of the control device; Fig. 4 is a vector diagramshowing the relationship of certainof the voltages; Figs. 5 and 6 are,respectively, a view, partially in section and partially in sideelevation, and a view, in end elevation, of a torque device andcontroller shown in Fig. 1, and Fig. 7 is a detail view of a portion ofsaid device; and Fig. 8 is a simplified View corresponding to Fig. l.

Referring to the drawings, the system shown comprises a source 1 and Gof singlephase alternating. current energy which is connected to aprlmary winding 2 of a transformer 8-having a secondary winding 4:; aphase converter 5 having a squirrel-cage rotor 6, an exciting winding 7and a secondary winding 8; a pluralityof electrically operatedtransformer switchesa .to Z, inclusive, which are divided into twogroups, one of which includes switches a to g, and is adapted to adjustthe connections of one terminal of the converter secondary winding 8with respect to substantially the middle portion of the transformersecondary winding 4 for the purpose of efiecting compensations for thephase distortion which is inherent in the converter 5, under loadconditions, and the second group of switches h to Z, inclusive,'beingadapted .to vary the connections of the exciting winding 7 with respectto the end turns of-the transformer winding 4 for the purpose ofadjusting the excitation of the converter 5; a polyphase dynamo-electricmachine 12 of the induction type having primary windings 13 andsecondary windings 14 and which isadapted to act either as a motorreceiving ener y from the converter 5 or as a generator elivering energyto the source 1 and G through the converter 5; a controller 16 forgoverning the circuit'connections of the electrically operatedtransformer switches a to Z, inclusive; a torque device 17 adapted torotate the controller 16 in either direction,

and embodying a plurality of primary windings 18 and 19, the winding 19having a constant excitation from an auxiliary transformer 20 which isconnected across a portion of the transformer winding 4, while thewinding 17 is energized in accordance with the current traversing theconverter secondary winding 8, whereby the torque developed'by thedevice 17 is responsive to the converter load. Th circuit connectionsare shown in a simplified manner in Fig. 8.

The specific details of the converter 5, dynamo-electric machine 12 andthe torque device 17 form no part of our present invention, thesedevices being illustrative of any suitable means for accomplishing theirrespective functions. The electrically operated transformer switches ato Z, inclusive, are preferably of the unit-switch type of any wellknown construction, and embody energizing coils a to l which, of course,are mechanically associated with the respec tive switches, although theyare shown separated therefrom in Fig. 2, for the sake of clearn'ess Theswitches 71, and Z are, moreover, provided with auxiliary contactmembers or interlock switches h andl which are shown directly beneaththerespective energizing coils h and Z, in Fig. 2 and operated whenevertheir corresponding switches are opened .or closed, in accordance withwell-known practice.

" secondary winding 8 to the preventive- A plurality of preventive'coils 22 and 23 are provided in the connections between the I converterwindings 7 and 8 and the transformer winding 4 to prevent a local shortcircuit upon any portion" of the transformer in the customary way, and aseries transformer 24 is associated with a conductor 25 which connectsone end of the converter coil 22, said transformer 24 being included inthe circuit with the winding 18 of the torque device 17, whereby theoperation of said device is rendered electro-responsive to the currenttraversmg the converter secondscribed, and the other end of WhlCll 1sary winding 8.

The dynamo-electric machine 12 has its ducting segment 34 and aplurality of cooperating stationary contact terminals 35 to 42,inclusive, which are adapted to engage the conducting segment 34 uponthe position-indicatinglines marked 0, Reg 1, 2 and Ace. 1,2, 3,dependent upon whether the dynamo-electric machine 12 is regeneratingenergy to the source or is bemg accelerated as a motor.

Referring particularly to Figs. 5, 6 and 7 the torque device 17 may beof any suitable construction for performing the func tions necessitatedby ourinvention, and may conveniently comprise. a torque motor or dynamoelectric machine 45having a stator 46 and a rotor 47 which is adaptedfor slow' rotative movement to a limited degree in one direction, undercertain conditions of load, and in the opposite direction under otherload conditions. The rotor 47 is provided with a shaft 48 which projectsoutwardly from both ends of the rotor 47 and carries, at one end, therotatable control drum 16 which cotiperates with its contact terminalsor fingers 35 to 42, which are suitably mounted in position. The rotorshaft 48 is mounted for rotative movement in end brackets 49 which areattached to the respective ends ofthe stator '46. One end of the rotorshaft 48 is provided with a plurality of torque opposing mechanisms 50,51 and 52, which are adapted to coiiperate with the shaft for thepurpose of imposing restraint upon its operation when it is rotated inone direction in response to load caused by motor operation of thedynamo-electric machine '12. The other end of the shaft 48 is providedwith similar torque-opposing mechanisms 54 and 55 which act in a similarcapacity when the regenerative action of the dynamo-electric machine 12causes the rotor 47 of the torque device 17 to be rotated in'the otherdirection.

The torque-opposing devices 50 to 55, inclusive, are of likeconstruction, except that the devices 54 and 55 are disposed in theopposite direction to the devices 50, 51 and 52, and each comprises abearing sleeve 60 which is fitted over the shaft 48, a ratchet 61,having an integral laterally projecting tubular member 62, aspiralspring 63 of flat strip material, one end 64 of which is secured to apart of a supporting and positioning structure 65, to be hereinafterdebracket 49 or is mechanically associated therewith, the arm beingdisposed substantially parallel to the shaft 48 and serving to restrainthe fingers 66 against the action of the several springs 63, under normal conditions, when the torque device 17 occupies its neutral position.A similar projecting arm 72 performs a like function for the fingers 66of the devices 54 and 55 that are associated with the other end of theshaft 48.

The type of spring employed is of particular importance in the operationof the torque device 17, inasmuch as it has a pcculiar property ofmaintaining a substantially uniform tension throughout a rela tivelylarge range of rotational movement of the shaft, as will hereinafter bemore fully pointed out.

The shaft 48 isprovided with a plurality of arms 7 5, 7 6 and 77 whichare fastened thereto and moved thereby. The arm is disposed adjacent tothe torque-opposing device 50 and is provided with a pin 78 whichprojects into the vertical plane of the finger 66 of the device .50,while the arm 76 is interposed between the devices 51 and 52 and isprovided with a plurality of pins 79 and 80 which respectively projectin opposite directions into the vertical )lanes of the devices 51 and52. The pins 8, 79 and 80 are also angularly displaced and, therefore,are adapted to be brought successively into engagement with the lowersurfaces of the outer ends of the fingers 66 when the shaft 48 isrotated in a counterclockwise direction, as viewed from the right-handend of the device.

For the purpose of separating the movable arms 75 and 76 from theadjacent devices 50, 51 and 52, and also for positioning said devices,the supporting structure 65 is employed, which is attached to the endbracket 19. The supporting structure 65 embodies a plurality of rods orbolts 82 and 83 which conveniently may be threaded into the bracket 19and are located in the v rtical plane of the shaft 48. A plurality ocross members 84-, 85, 86 and 87 are associated with the bolts 82 and 83and are provided with openings through which the shaft 8 projects. Thesecross members 1-, 85, 86 and 87 are suitably spaced apart by sleeves orspacing members 88 of suitable lengths to definitely locate thesemembers so asto separate the arms 75 and 76 from the adjacenttorque-opposing devices 50, 51 and 52.

The arrangement of parts of the supporting structure and other elementsassociated with the opposite end of the shaft 48 is sim ilar to thatjust described, except that only two torque-opposing devices 54 and 55are provided. The control drum 16 is carried by the shaft 48, and thestationary contact terminals or fingers 35 to 42, inclusive, aresuitably mounted upon a supporting member 89 for coiiperative engagementtherewith.

For purposes of protection, a plurality of inclosing casings 90 and 91are provided and associated withthe end of brackets 49.

Before describing the operation of the system, it is deemed advisable toset forth the operation of the torque device 17, independently of itsrelationship to the rest of the system.

Assuming that the apparatus occupies the position shown, with theseveral springs 63 properly adjusted for the desired tension, forinstance, 3 lbs, and that the dynamoelectric machine 45, or any othertype of torque apparatus, be caused to develop a torque tending torotate the shaft 48 in a counter-clockwise direction, as viewed from theright-hand end thereof, the operation is as follows: The pin 80 of thearm 76 is at once brought into engagement with the finger 66 of thetorque-opposing device 52,

and further movement of shaft i8 is, there fore, prevented until thetorque apparatus develops a torque in excess of the tension of thespring. Thereupon, the torque apparatus overcomes the action of thespring 63 and moves positively and comparatively rapidly until the pin79 is brought into engagement with the finger 66 of the torqueopposingdevice 51. When this engagement is effected the device 51 becomes activeand adds the tension of its associated spring 63 to that of the springalready in action. Thus, the combined action of the springs of thedevices 51 and 52 imposes a restraint upon the torque apparatus of sixpounds and prevents further movement until said apparatus develops atorque sufiicient to overcome the opposing springs. Under theseconditions, the torque apparatus and shaft 48 are at once moved througha definite angle until the spring 68 of the device 56 becomes active andprevents further rotative movement. In the'same manner, the apparatus ispermitted to move to its neXt position when the torque developed exceedsthe opposing tension of nine pounds of the three springs 63 actingtogether.

Thus, the apparatus is caused to occupy a series of definite posi ions,and, moreover, to be moved from one position to the other withpositiveness and quickness. By reason of the property of uniform tensionof the springs (33, throughout a wide range, the positions .of thetorque apparatus and its associated control drum 16 are rendereddefinite, and a step-by-step movement thereof is effected. As theoperation in the opposite direction is carried out in a similar manner,no description thereof is deemed necessary.

The operation of the system will now be set forth and particularreference may be had to Figs. 1, 2, 3 and 4. Assuming the torque device17 and the controller drum 16 to occupy their neutral position marked O,as shown in Fi 2, a circuit is established from one side of the batteryB, or other suitable source of energy, which includes stationary contactterminals 42 and movable conducting segment 34, where the circuitdivides, one branch traversing contact terminal 38 and thence, throughthe energizing. coils (Z and j, in parallel, to

the negative side of the battery B, while another branch includescontact terminal 37 and thence through energizing coil 0 to the battery'and through interlock switch it out and energizing coil z" to thebattery. Upon the energization of the coils (Z, 0, 2", and 7", theircorresponding switches c, d,

i and are closed to connect the converter exciting winding 7 across themajor portion of the transformer winding 4 and the converter secondarywlnding 8 to substantially v the mid-point thereof. The preventive coils22 and 23 serve their usual function to prevent a local short-circuitacross the portions of the transformer winding 4 between the switches aand d, and 2' and j, said coils 22 and 23 being connected directly inparallel to these transformer sections.

Under these conditions, balanced threephase voltages are delivered tothe bus-bars or conductors 30, 31 and 32, provided, of course, that theconverter 5 is designed to produce a voltage across its secondarywinding 8 which is substantially'S6.6% of the normal voltage of thetransformer winding 4, in accordance with the well-known Scott or Tconnection. The voltage relations are shown in Fig. 4, E representingthe voltage of the transformer winding 4, E the voltage of the converterwinding 8, and X and Y the other phase voltages of the three-phaseenergy of the bus-bars 30, 31 and 32.

Suppose, now, that the switch 29 is closed to connect thedynamo-electric machine 12 to the bus-bars 30, 31 and 32 and that thestarting resistance device 28 is operated to exclude resistance fromsecondary windings 14, whereby the motor 12 is brought up to speed; whenthe motor 12 is operated at light or no load, the voltage relationsremain as described, but, when the motor 12 begins to take on its load,there is, by reason of the reactive drop in the converter 5, a tendencyto distort the phase position thereof and to effect a reduction in theconverter voltage E If the automatic torque device 17 were not As themotor 12 gradually takes on its I load, the current traversing theconductor 25 wlth which the serles transformer 24 1s associated,increases 1n amount, and, hence,

a torque is developed in the torque device 17 that tends to rotate saiddevice and its associated control drum 16in a predetermined direction,which. is assumed to be counter-clockwise when referring to Fig. 5.

When the torque developed becomes suflicient to overcome the tension ofthe first spring 63 of the torque-opposing device 52, the drum 16 ismoved intoposition marked A00. 1. Thus,a circuit is established from theconducting segment34 of the control drum 16 through contact terminal 39and thence, through a branch including the energizing coil 6, to thebattery, and, through another branch including the interlock switch Zout and energizing coil is to the battery. Thus, switches e and 7a areclosed. Concurrently with this action, contact terminal 37 is disengagedfrom the conducting segment 34 and, hence, energizing coils c and i areopen-circuited, and their corresponding switches a and i are opened-Itis seen, therefore, that the connection of the converter secondarywinding 8 is shifted to the right of the mid-point of the transformerwinding 4, whereby the converter distortion is corrected, while theconnection of the exciting winding 7 is also shifted to the right,thereby increasing the converter excitation and, consequently, restoringthe converter I voltage to its initial value. Thus, balanced loadconditions are maintained, and corrections in the amount and phaseposition of the voltage are automatically efi'ected.

When the load on the motor 12 increases further to an amount sufficientto cause the torque of the torque device 17 to overcome the combinedeffect of the springs 63 of the torque-opposing devices 52 and 51, thecontrol drum 16 is positively moved into its next position marked A00.2.

This action causes the control drum conducting segment 34 to be broughtinto engagement with the contact terminal 40 and thus to complete acircuit therefrom, one branch of which includes the energizing coil f"and the other includes energizing coil Z, whereby the switches f and Zare closed. During this action, contact terminal 38 disengages theconducting segment'34 and hence, deenergizes coils d and j and permitsthe opening of the corresponding switchesd and j.

It will be noted that the connections of naaasea the converter windings'Z and 8 to the transformer winding thave been shifted again to theright, whereby corrections for distortion and for reduction inexcitation are efieeted.

In case of further increases in the motor load sufiicient to overcomethe combined action of the three springs 68 of the torque opposingdevices 50, 51 and 52, the controller drum 16 is caused to move-anothernotch marked Ace. 3, and switch 9 is closed and switch 6 opened, whilethe switches 76 and Z are maintained closed.

The action, therefore, is entirely automatic, and the converterconnections to the transformer winding 4 are adjusted in response toload conditions to effect automatic compensations for the phasedistortion and voltage reduction.

Under certain conditions of operation, particularly it the system isused in connection with an electric railway vehicle or with afiywheel,it is evident that, at times, the machine 12 will be driven as agenerator by the inertia of the rotating parts, and will regenerateenergy through the converter 5 in the reverse direction to the source1-G. Inasmuch as the current through conductor 25 is thus reversed indirection, the edect upon the torque device 17 is to reverse itsdirection of operation and move it into one of its regenerationpositions, marked Reg. 1 and 2. @therwise, it operates, in themannerherein set forth, to rotate the control drum 16 and toautomatically effect the necessary compensations for phase distortionand voltage reduction in accordance with the regenerated load.

On account of the similarity of operation of the system, underconditions when the dynamo-electric machine 12 operates as a generator,to that hereinbefore described, it is believed that no difficulty willbe experienced in understanding the action and, hence, no descriptionthereoi is deemed necessary. it will, of course, be understood that,during the regenerative period, the distortion of phase position is inthe opposite direction to that already discussed in connection with themotor operation, and voltage change is an increase instead of decrease,the point moving 1 A Tough We have shown and described our invention asembodying a specific arrangement of parts circuit connections, and inconnection with a torque device of a specific will be understood oninvention is broadly applicable 'tcsystems and apparatus diffewidelyfrom that which we have chos i or iilustrative pur poses, and desire tit only such iimita tions shail be imposed indicated the appended ciains.

We claim as our invention:

1. The combination a singie-nhaee source of energy, a polyphasedynamo-electric machine and phase-converting means connected betweensaid source and said dynamo-electric machine, of auxiliary meansresponsive to load conditions for adjusting the connections of saidconverting means in accordance with the generator or the motor operationof said dynamo-electric machine.

2. The combination with a single-phase source of energy, a polyphasedynamo-electric machine and phase-converting means connected betweensaid source and said dynamo-electric machine, of automatic meansembodying a single actuating memher for regulating the operation of saidconverting means in accordance with the generator or the motor operationof said dynamoelectric machine.

3. The combination with a single-phase source of energy, a polyphasedynamo-electric machine and'phase-converting means connected betweensaid source and said dynamo-electric machine, of a plurality ofelectrically controlled switches for efiecting the connections betweensaid converting means and said source, an auxiliary control apparatusfor governing the operation of said switches," and a singleelectro-responsive device for actuating said control apparatus inaccordance with the generator or the motor operation of saiddynamo-electric machine.

4. The combination with a single-phase source of energy, a phaseconverter and a dynamo-electric machine adapted to act as a generator oras a motor, of automatic means for maintaining predetermined phaserelations, irrespective oi the nature of action of said dynamo-electricmachine.

5. The combination with a single-phase source of energy, a phaseconverter and a dynamo-electric machine adapted to act as a generator oras a motor, of electro-responsive means for adjusting certainconnections of said converter to one portion of source when said machineis loaded as a n1o= tor and to another portion when said machine isloaded as a generator.

6. The combination with single-p iase transformer windin phase conv fand a dynamo-electric machine energy from said converter, res, cc .1, orautomatic means for adjusting the connections of said converter to oneside of pred termined points in said winding when dynamo-electricmachine is operated as I motor and to the other side of said predetermind points when the machine is onerated as a generator, said means beingaspcnsive to load conditions and adapted to maintain baianced conditionsupon said phase converter.

T. The combination with a source of en ergy, a phase converter havingone winding connected across said source and another windlng connectedto substantially the midpoint of said source, and a dynamo-electricmachine adapted to receive energy from said phase converter, ofautomatic means embodyinga single torque motor responsive to loadconditions for shifting the connections of said phase converter withrespect to said source to vary the excitation and the phase position ofsaid phase converter during both connecting the other winding acrosssaid source, of a switching device adapted to govern the operation ofsaid sets of switches, and a torque device depending upon the nature andamount of load for adjusting said switching device.

9. The combination with a single-phase source of energy, a phaseconverter and a dynamo-electric machine adapted to act as a generator oras a motor, of a torque device having actuating coils respectivelyenergized in phase with said source and in accordance with the currenttraversing a certain converter circuit, and switching means controlledby said torque device for varying the connections between said sourceand said converter in accordance with predetermined circuit conditions.

10. The combination with a single-phase source of energy, a phaseconverter having a primary winding energized in phase with said sourceand a secondary winding connected to an intermediate point of saidsource, and a dynamo-electric machine connected to said converter andadapted to act as a generator or as a motor, of a torque device havingactuating coils respectively energized in phase with said source and inaccordance with the current traversing said converter secondary winding,and switch- J ing means controlled by said torque device for varying theconnections between said source and said converter to vary theexcitat1on and correct the phase distortion of said converter undervarying c1rcu1t conditions.v

11. The combination with a single-phase transformer winding, a phaseconverter having a primary winding connected in circuit with saidtransformer winding and a secondary w1nd1ng connected to an intermedlatepoint of said source, and a dynamoelectric machine connected to saidconverter and adaptedto act as a generator or as a motor, of a'torquedevice having actuating coils respectively energized in phase with saidtransformer winding and in accordance withthe current traversing saidconverter secondary winding, and switching means controlled by saidtorque device for adjusting certain connections of said converter to oneportion of said transformer winding when said machine is loaded as amotor and to another portion when said machine is loaded as a generator.

12. The combination with a single-phase transformer winding, a phaseconverter having a primary winding connected in circuit with saidtransformer winding and a secondary windingconnected to an intermediatepoint of said source, and a dynamo-electric machine connected to saidconverter and adapted to act as agenerator or as a motor, of a torquedevice having actuating coils respectively energized .in phase with saidtransformer winding and in accordance with ondary winding, a pluralityof switches, severally having actuating coils, for effectingconnectionsbetween said converter and said transformer winding, and contact memberscontrolled by said torque device for se- KARL A. SIMMON. ARTHUR J. HALL.

Witnesses H. T. MORRIS, B. B. HINES.

.80 the current traversing said converter sec--

